ELECTRICAL AND ELECTROMECHANICAL PROPERTIES OF PbZr03-PbTi03- PbMg1/3Nb2/303

Ceramics of nominal composition 0.35·PbTi03-0.25·PbZr03-0.375·PbMg1 /3Nb2/303 (PZT-PMN) were prepared using two methods. In one the elemental oxides (PbO, Zr02, Ti02, Nb20S and MgO) were mixed, calcined at 900 ac, and then sintered at 1200 °C for 2 hours. In the second, the MgO and Nb20S were calcined beforehand at 1000 °C to obtain the columbite structure which was then mixed with the other oxides. This route eliminates the formation of pyrochlore in the sintered ceramic. The polarization and density of PZT-PMN, prepared using the columbite route were higher and the coercivity was half of ceramic prepared using the single step calcination. The poling field dependence of the electromechanical coupling factor (kp) and the mechanical quality factor (OM) were also measured and are discussed.